An electrical connector assembly generally includes matable plug and receptacle members, each member including a housing of insulative (or dielectric) material having cavities within which electrical contacts of conductive material are retained. In these assemblies, the contacts are electrically terminated to a wire which extends rearwardly/outwardly from the respective cavity. Were no restraint means to be provided to the wires, soldered or other conductor terminations would be constantly vulnerable to interruption by stresses resulting from both radial and axial forces placed on the wires. To safeguard against such separation of wire conductors from their associated contacts, a number of strain relief devices have been provided in the past.
In cylindrical-shaped connectors having a primary axis, the terminated wire positions are radially clustered fairly closely together about the connector axis. To prevent loose wire movement from injuring the electrical termination, the loose wires are typically bunched together and tightly secured into a bundle by a cable tie. Bundling, however, forces the wires to deflect radially from their axes and places both axial and lateral loads on the electrical termination. One solution disclosed by U.S. Pat. Application S.N. 16,719 registered the contact cavities with apertures in a rigid disc spaced axially rearwardly of the connector member and passed each terminated wire through the respective aperture. While suitable for the purpose of eliminating radial wire deflection, this apparatus would not necessarily eliminate the effect of axial forces. As the number of contacts employed in a connector increases, so does the minimum force to disengage the connector as well as a likelihood that a user in the field will pull on the wires to assist in disengagement of the connector. Accordingly, a more desirable apparatus would restrain a terminated wire from both radial and axial movement.
The electronics industry is tending more and more towards circuitry being printed and/or components used therewith being arranged on a generally rectangular shaped board with electrical interconnection locations being spaced along one or more edges of the board. Accordingly, a suitable connector must advantageously space a plurality of discrete contacts in a parallel, side-by-side relation. As the board length and the number of interconnection points on the board increases, linear separation between a connector's outermost wire connection points would also increase thereby resulting in the wires not being clustered closely together. In such a case, if each of the discrete wires were to be bundled together, radial wire deflection would place undue strains on the wire/contact termination. Further, during disengagement, a user would again have a natural tendency to want to tug on the plurality of wires and axially strain the wire terminations.
Unrestrained wires undergo lateral deflection just due to their weight. This would be true whether flat (ribbon) cable or discrete wires were utilized. When these wires pass through a moisture sealing grommet passage, lateral deflection of the wires could deflect the grommet passage, allowing moisture to enter the passage and short out a circuit.
Simple cable clamps are known. However, by exerting clamping pressure on opposite sides of a cable, problems have developed in the past, such as a shorting of conductors with the clamping means. Plastic ribbon conductors, for example, are typically embedded in polyethelene-terephthalate, a material subject to pressure called cold flow. As a result, either during assembly or after installation, a high risk is presented that the clamping pressure will cause an extrusion of the plastic cable insulation from a conductor or conductors with a concomitant shorting of the conductors with the clamp.
Accordingly, it would be desirable to provide apparatus that secures a plurality of wires terminated to contacts in spaced apart substantially side-by-side relation, that prevents both radial and axial deflection of the terminated wires, that eliminates or reduces forces acting on the electrical termination and that prevents lateral wire movement from deflecting a grommet passage and thereby allow moisture to enter the connector assembly and short out the contact-to-wire termination.